Kidder, 69, became a household name in 1978 for her role in "Superman: The Movie" opposite Christopher Reeve, but also fought manic depression that left her homeless in the late 1990s, People reported. The star later became an advocate for mental health awareness.

"She had no qualms about being who exactly she was, saying things very much out loud wherever she was," Kidder's longtime friend Cara Wilder told People. "She survived so much, she came from the wilds of Canada and survived all these different lives. We were very politically active so we had that in common.

"She loved the theater still and she was so good and so sharp on stage and such an amazing presence. She was such a strong woman. Ironically a colleague and I were just getting in touch with her the last few months about doing a documentary of her life and she wanted to do that," Wilder added.

She also was close friends with actress Carrie Fisher, who played the iconic Princess Leia in the "Star Wars" franchise before dying in late 2016.

"She was close to Carrie Fisher," Wilder told People. "There was a lot of death in her life lately and she felt the weight of that. We had a close friend pass away a week ago, I talked to her on Friday and she said that was hard to process. She said, 'I think there's going to be a lot more death like that happening."

Rest In Peace Dear #MargotKidder ❤️ I was such a fan of yours from the first moment I saw you on the screen as Lois Lane in Superman! I will treasure the moment that I met you forever! Sweet dreams Margot🌤